Molded rubber bushing for yarn twisting spindle mechanism



April 14, 1953 J, K, COCHR 2,635,019-

MOLDED RUBBER BUSHING FOR YARN TWISTING SPEENDLE MECHANISMS Filed Oct.5, 1948 INVENTOR JOHN K. COCHRAN ATTORNEYS Patented Apr. 14, #1953MOLDED RUBBER BUSHING roa YARN 'rwrs'rmq SPINDLE MECHANISM 7 John K.Cochran, Conyngham, Pa., assignor to The Duplan Corporation, Hazleton,Pa., a corporation of Delaware Application October 5, 1948, Serial No.152,936

This invention relates to the spinning and twisting of textile yarns andparticularly to the bearing supporting bushing in the spindle assemblyused therefor. V

In spinning and twisting textile yarns, particularly in imparting doubletwist to textile yarns strands, a hollowed spindle is used through whichthe strand of yarn passes in an over end relationship. The yarn isemitted from the lower end of the spindle and thence passes upwardly wetakeup reel located above the spindle. The.

' commercial assembly normally comprises a cylindrical support for thesupply spool within which the double'twist spindle rotates at highspeed, the yarn package and its cylindrical support remaining relativelystationary.

Such a structure necessitates, of course, the use ofs'uitable bearings.The inner race of the bearings is firmly attached to the spindle whichis rotatable" while the outer race of the bearings is firmly attached toa bushing which is one of the relatively stationary parts. A metalbush-'- ing may be machined and it will be apparent that such machiningnecessitated very close tolerances. The bushing must constitute asufficiently firm support'to prevent the outer race from rotating whileat the same time it must not exert an excessive inward pressure on thebearing since such pressure would distort and deleteriously affect theoperation of the bearing. Close tolerance manufacture of the bushing, ofcourse, greatly increases the cost of the assembly. Furthermore, closetolerances are not required inflthe remaining parts of the assembly. Therequirements of such a bushing constitute a problem in the industry.

Therefore, it is'the object of this invention to provide new andimproved apparatus for supporting the bearings in a textile yarn spindleassembly.

Other objects will be apparent after a study :of the followingdescription, claim and drawings, in which- Figure 1 is a. sideelevational view of a complete spindle assembly with portions thereofpartially cut away and in cross-section to illustrate the inventionwithin the assembly; and

Figure 2 is a sectional view through 22 of Figure 1.

A complete yarn twisting spindle assembly is illustrated in Figure 1except that the yarn supply spool and the takeup spool are not shown.The cylindrical tube I2 comprises the supply spool support. The yarnpasses downwardly through the upperportion of the cylindrical member I2and through the hollowed spindle II lClaim. (01. 308-184) and is emittedat the lower portion of the spindle:

normally at the storage ring I3. The storage ring I3 together with theyarn guide disc I4 arefirmly attached to the spindle so as to'be rotat--abletherewith. The spindle II rotates at high. speed while thecylindrical tube member I2 re'- mains relatively stationary.

Normally two bearings are provided for supporting the cylindrical tubeI2 and its associated parts on the rotatable spindle I I. Otherbearings. might be used if desired. An upper bearing 2I,: which may beeither ball bearing or roller bear ings, isprovided between the upperend of the shank 22 of the spindle II and the bushing 23'. mountedwithin the cylindrical tube I2 for the The inner purpose of supportingthe bearings. race 24 of the bearing is firmly attached'to the shank 22of the spindle II. The outer-race 25 of the bearing is firmly supportedby the bushing.

Like the upper bearing 2I the lower bearing 32 may be roller or ballbearing as desired. The inner race 34 is firmly attached to shank 22 ofspindle II and the outer race 35 is attached to bushing 23.

Conical grease retainers 31 and 38 may be provided, respectively, forthe upper spindle 2I and the lower spindle 3 I, as desired.

The bushing 23 is cylindrical with the outer diameter thereof conformingto the inner diameter of the supporting tube I2. The particular shape orform of the bushing is not critical and may be varied as desired. Thereis an opening in the upper end of the bushing for the shank 22 of thespindle I I. Preferably the lower end of the bushing 23 is arranged soas to extend beneath the lower edge of the cylindrical supporting tubeI2 to some extent and thus provide a more secure mounting. The bushing23 may be keyed to the supporting tube l2 by one or more radialprojections M from the outer surface of the cylinder. A complementaryopening is provided in the cylindrical tube I2 to receive the projection4|.

It is apparent that, unless the bushing 23, if it were metal, were to bemachined accurately with 'close tolerances, either undue and distortingpressure on the hearings or slippage of the bearings would result. Ineither instance the bearings would not operate satisfactorily. Inaccordance with this invention there is provided a molded rubber.bushing. In the interior and upper end of the bushing 23 a suitableshoulder is provided against which the outer race of the bearing 2|abuts. A second shoulder is provided at the lower 3 end of the bushingfor location of the lower hearing 3|. The outer diameter of the bushing23 conforms generally to the inner diameter of the cylindrical tube I2with a resulting close or presporting the bearings 2! and 3 I. If thepressure istoo great for the bearings, it is; taken up by the" resilientinherent characteristics of the, molded rubber bushing. Thus there issufficient pressure to retain the outer race of the bearings instation-- ary position while at the same time theresiliency of thebushing prevents the pressure from being excessive so that there is noundue or distorting pressure on the bearing which will prevent properoperation thereof. The outer race of thebearing is prevented fromrotating. Because of the resilience of the' bushinggit "need not bemaintained to close tolerances" in production. With this arrangementeachof the bearings 21 and 3| is retained firmly but: gently in position.The rubber bushing should beoil resisting in view of the presenceof oiland grease for the rotating metal parts.

Thisarrangement of amolded rubber bushing for the. bearings ofarotatable spindle in a yarn twisting assembly has proved to be a.satisfactory solution to the bearing. supporting problem. While thepreferred embodiment has been illustrated: and.v described, it will beapparent to those skilled in the art that modifications are possiblewithout; departing from the scope of the invention.

What is claimed is;

Apparatus for spinning and twisting textile yarns comprising a rotatablespindle coaxilly mounted within a relatively stationary cylindricalmember, a. molded rubber cylindrical bushing positioned ,coa-xially'between said spindle and said cylindrical member, the outer diameter ofsaid bushing conforming to the inner diameter of said cylindrical memberforming an inner lining therefor, the inner diameter of said bushingbeing greater than the outer diameter of said spindle, the longitudinallength of saidbushing being more than half the longitudinal-length ofsaid spindle and less than the longitudinal length of said cylindricalmember, the lower edge of said bushing extending beyond and beneath thelower end of said cylindrical member, said bushing havinganop'ening inthe upper end thereof for said spindle, a. radial. projection from theouter surface ofisaidbushing extending into a complementary opening insaid'cylindrical member to retain said bushing in position, preventingrelative rotation between said bushing and said cylindrical memher, theinner surface of said bushing having a first annular supporting surfacenear the upper end thereof with a shoulder along the edge of saidsurface, a second'annularsup'porting surface near the lower end ofsaidbushing andwith a shoulder along the edge thereof, a first unitarybearing structure having an inner race and an outer race mounted withinsaid bushing and retained by'annular resilient pressure of one of saidsupporting surfaces against said outer race, and asecond unitary bearingstructure having an inner race and an outer race mounted within saidbushing near. the other end thereof and; retained by annular pressure onthe other of said supporting surfaces against the second saidouterrace'.

JOHN COCHRAN.

References Cited in the. file or this patent UNITED STATES PATENTSNumber Name Date 2,044,392 Lord s June 16, 1936 2,149,122 McCal1- s Feb.28, 1939 2,201,477 Chamberlain May'2l, 1940 2,261,823 Ballard l Nov.-4,1941

